A maximum-security prison in Central California that serves as the setting for this song, Folsom Prison sparked Johnny Cash's real-world interest in doing a prison tour.
Shortly after Cash penned this song (while serving in the Air Force in Germany), he released it on Sun Records, where it gained moderate success. The inmates at the Texas State Prison in Huntsville heard the song and wrote Cash to ask him to put on a prison show for them. The memorable concert that resulted led to a series of Cash performances behind bars, as he later recalled in an interview with Larry King:
And this was 1956 I got the invitation to do a concert at Huntsville, Texas. So the Tennessee Two and I, Marshall Grant and Luther Perkins and I went down to Huntsville, Texas and set up in the middle of the rodeo arena. They had this big rodeo every year…Well, we did 'Folsom Prison Blues' and it started raining, and a thunderstorm hit. We were right in the middle of the arena and the rain is pouring down on our one little amplifier. In the middle of the song it burns out. And I got no amplification, none whatsoever. And there's thunder and lightning all around me. The men have been told not to leave their seats but they all do. They all do. They walk down in the rain to get close enough to hear me sing without the amplifier. And I sang that song, and they demanded that I sing it again and again. We all got soaking wet, but we had a great time. But after that, Larry, I got a request from San Quentin, from the word got around the prison grapevine that I was one of them I guess. But the word got around in San Quentin, and they have that New Year's Day show every year. I was invited to perform at that. So I started—I made that an annual event for about five years. (Source)
Country slang for San Antonio, which is of course a major city in Texas.
First inhabited by Native Americans, and later by Spanish missionaries who named it after the Portuguese saint, St. Anthony, San Antonio was the site of the famous Battle of the Alamo in the Mexican-American War.
Growing up in the South, Cash was much more familiar with that part of America than he was with California, the site of Folsom Prison. Speaking through the prisoner in the song, Cash imagines that the train rolling through central California is destined for the South and will eventually pass through San Antonio, perhaps a town that holds a special place in his heart.
But I shot a man in Reno
Just to watch him die
This is arguably the most famous and controversial line in the song.
When asked about the genesis of this line, Cash claimed that he sat trying to think of the worst reason a man could have for killing another person and this is what sprang to mind.
When the single was re-released in 1968 from the live album At Folsom Prison, the maverick producer, Bob Johnston, dubbed in a prisoner cheering after those words, adding even more controversy to the line. It was taken out of the song completely after the assassination of Robert Kennedy in order to not offend the mourning nation.
A minor logical flaw with the lyric is that if the prisoner shot a man in Reno, then he would be presumably end up in jail in Nevada, not California. But we can probably give Johnny Cash a little poetic license here.
I bet there's rich folks eatin'
In a fancy dining car
They're probably drinkin' coffee
And smokin' big cigars
Cash actually didn't come up with the original idea for this song; instead, he expanded on a little-known song called "Crescent City Blues" by Gordon Jenkins. This verse is almost identical to Jenkins' lyrics.
Jenkins' verse reads as follows:
I see the rich folks eatin' in that fancy dining car
They're probably having pheasant breast and eastern caviar
Now I ain't crying envy and I ain't crying me
It's just that they get to see things that I've never seen
Not a huge difference, although Cash focuses more on the vices of caffeine and nicotine rather than fine dining, which may hint subtly at his addictive personality and later battles with drugs. The lyric also works well for Cash because he grew up in a working-class family who could only imagine what the privileged rich folks might be doing in their exclusive car.
Although Johnny Cash is famous for his unique singing style and voice, many different genres influenced his musical career, prominent among them the blues.
The blues, along with jazz, are the only two musical genres native to the United States. The blues were invented by African-American musicians in the Deep South in the early 1900s. Railroad songs, blues, and country were all huge influences for "Folsom Prison Blues." A resource detailing the history of the blues explains it like this:
The origins of blues is not unlike the origins of life. For many years it was recorded only by memory, and relayed only live, and in person. The Blues were born in the North Mississippi Delta following the Civil War. Influenced by African roots, field hollers, ballads, church music and rhythmic dance tunes called jump-ups evolved into a music for a singer who would engage in call-and-response with his guitar. He would sing a line, and the guitar would answer.
The Blues...it's 12-bar, bent-note melody is the anthem of a race, bonding itself together with cries of shared self victimization. Bad luck and trouble are always present in the Blues, and always the result of others, pressing upon unfortunate and down trodden poor souls, yearning to be free from life's' troubles. Relentless rhythms repeat the chants of sorrow, and the pity of a lost soul many times over. This is the Blues. (Source)